Diazotype layer containing acetoacetamido coupling components



United States Patent 3,387,977 DIAZOTYPE LAYER CONTAINING ACETO- ACETAMIDO COUPLING COMPONENTS David P. Habib, West Springfield, and George R. Hodgins,

South Hadley, Mass, assignors to Tecnifax Corporation, Holyoke, Mass., a corporation of Massachusetts No Drawing. Filed Mar. 31, 1964, Ser. No. 356,024

6 Claims. (Cl. 96-91) ABSTRACT OF THE DISCLOSURE Diazotype sensitized material having a light sensitive layer comprising a light sensitive diazonium salt and an acetoacetamide derivative of an aliphatic amine containing the group:

Y H C-X wherein Y is oxygen or sulfur, X is selected from the group consisting of R OR, N

and a nitrogen bearing heterocyclic saturated ring containin not more than 7 atoms, and n is any integer from 1 to 3.

As is well known, acetoacetamido derivatives of aromatic amines may be used to obtain yellow and orange azo dyes by reaction with suitable diazonium salts. For example, an orange dye may be produced by react on of acetoacet-o-toluidide with 4-diethylamino-Z-ethoxy-benzenediazonium chloride. Yellow may be produced by reaction of acetoacetanilide with 4-ethylamino-3-methylbenzenediazonium chloride. Both these couplers are acetoacetamido derivatives of aromatic amines. Various other types of couplers and diazos for producing different colors are described in US. Patents Nos. 1,989,065; 2,494,906; 2,537,106; 2,537,919 and 3,069,268.

Since acetoacetamido derivatives of aromatic amines are characterized by high coupling activity with diazonium compounds, even in the presence of common stabilizers their use is limited, because diazo-sensitized materials in which they are used exhibit poor shelf life (i.e. tendency to pre-couple). Moreover, the acetoacetamido couplers heretofore available are unsuitable for formulating a good neutral black color. Part of the reason for the poor formulating quality of the aromatic acetoacetamides is the large difference between their coupling activity and that of the blue color-formers used in conjunction with them to obtain a black azo dye.

Attempts have been made to circumvent the disadvantages of poor shelf life and high coupling activity through the use of a partial replacement of this coupler class by a sepia color-former (e.g., US. Patent No. 2,537,919). The results, however, have not been entirely satisfactory.

Although the use of the acetoacet derivatives of aliphatic and heterocyclic amines was claimed to give acetoacet couplers improved shelf life and formulating qualities (e.g. US. Patent No. 2,537,106), the shelf life of diazo blackline products formulated with the coupler classes described therein is still less than satisfactory. The problem of providing acetoacetamido couplers having both good formulating quality and shelf life remained.

It is the principal object of this invention to provide improved couplers for use in the diazotype process.

It is another object of this invention to provide novel acetoacet couplers having markedly better shelf life in diazotype formulations than those heretofore known.

3,387,977 Patented June 11, 1968 ice It is a further object of this invention to provide improved diazo formulations for neutral blackline materials having prolonged shelf life with minimum background discoloration.

-We have found that compounds represented by the following general structure exhibit improved shelf life and produce neutral black shades, when used in conjunction with certain blue color-formers in a diazotype formulation.

Y II [ll omoomcNoHo-n C-X in which n is any integer from 1-3; X is selected from the group consisting of:

on, N

and a nitrogen-bearing heterocyclic saturated ring containing not more than 7 atoms; Y is oxygen or sulfur, and R is H or an alkyl group containing 1 to 4 carbon atoms.

Examples of acetoacet derivatives of aliphatic amines suitable for use in practicing this invention are: acetoacetamide of lycylamide, Z-acetoacetamido propanediamide, acetoacetamide of glycine methyl ester, and acetoacetamido thioglycylamide.

It has been found that acetoacetamido derivatives of aliphatic amines containing the group where Y=O or S, and X selected from the group consisting of:

on, N

and a nitrogen-bearing heterocyclic saturated ring containing not more than 7 atoms; have improved shelf life and slower coupling activity, closely resembling that of the blue color-formers. The yellow and blackline diazotype formulations embodying this invention indicate that these formulations have excellent shelf life and the blackline prints exhibit stability and greater resistance to background yellowing.

Apparently, the presence of the substituent effectively lowers the coupling activity of acetoacet couplers such that during shelf aging they have approximately the same coupling activity as those couplers normally used in blue and sepia formulations of blackline products. Thus shelf stability is greatly enhanced.

Acetoacet compounds embodying this invention may be synthesized by the reaction of a selected amine with diketene or acetoacetic ester. The following examples are illustrative of the method of synthesizing the type of acetoacet couplers suitable for the purposes and objectives of this invention.

EXAMPLE I 3.0 g. of glycine ethyl ester were dissolved in 10 ml. of acetone and a drop of pyridine was added. The solution was cooled to 0 (3., 2.7 g. of diketene in 5.5 ml. of acetone were then added slowly. After the reaction was completed, the mixture was cooled, and 2.1 g. precipitate of acetoacetamide glycine ethyl ester were recovered.

The acetoacetamide recovered was found to have a melting point 53-5 6 C., and its chemical composition was verified by intra-red spectrum analysis. This compound may be represented by the following chemical structure:

O t u CH3 CH NCHzC-OCzH EXAMPLE II Aminoacetamide, (3.7 g.), was slurried in a solution of 60 ml. of acetone and 5 drops of pyridine, and cooled in a Dry Ice bath. Diketene (6.98 g.) was then added all at once. The temperature rose rapidly. After the initial exothermic reaction had subsided, external cooling was removed and the temperature was allowed to rise to 30-45 C. A heavy white precipitate formed. After cooling, filtering, and washing with acetone 7.8 g. of 2- acetoacetamido acetamide having a melting point of 160- 161 C. were recovered. This compound, verified by infrared spectrum analysis, may be represented by the following chemical structure:

0 0 lg n H IL CH CH CNCH (,NH 2-acetoacetamrd0 acetamide EXAMPLE III N,N diethy1-2 amino acetamidezHCl (4.5 g.) were dissolved in 25 ml. of methanol and 1.44 g. of sodium methylate were added. After a few minutes stirring, the precipitated salt was removed by filtration.

Acetone ('25 ml.), and 3 drops of pyridine were then added. Diketene, 2.55 g., was added dropwise at ambient temperatures. The solvents were removed in vacuo and a light amber oil formed weighing 5 g. This compound, checked by infra-red spectrum analysis, may be represented by the following formula:

CzHsZ-tlcetoacetarnido CzHsN', N dicthylacctamide EXAMPLE IV 3 g. of 2amino malonamide were mixed with 50 ml. of acetone and 5 drops of pyridine. The mixture was cooled to 0 C. and 8.2 g. of diketene in drops were added. The temperature was maintained at 0 C. with a cooling bath. After the addition of diketene had been completed, the mixture was heated to reflux for 30 minutes. The mixture was cooled to 20 C. and a white precipitate formed. After filtering and drying 3.7 g. of Z-acetoacetamido propanediamide were recovered having a melting point of 164467 C. This compound, verified by infra-red spectrum analysis, may be represented as follows:

H II II 0113C CII CNCII 2-acotoa'etarmdcpropaucdiamido Insofar as is known, no limitation is imposed on the selection of diazo compounds arising out of the use of the aliphatic acetoacet compounds embodying this invention. The following are examples of diazonium compounds which may be used with the acetoacet couplers embodying this invention to manufacture light sensitive diazo coating compositions:

4-N,N-diethylamino benzenediazonium chloride 4-N-methyl-N-hydroxyethylamino-benzenediazonium chloride 4-N,N-dimethylamino-benzenediazonium chloride 4-N-ethyl-N-hydroxyethylamino-benzenediazonium chloride 4-N-ethylamino-benzenediazonium chloride 4-N,N-diethylamino-2-methylbenzenediazonium chloride 4-N-morpholino-2,S-diethoxybcnzenediazonium chloride 4-N,N-bis-(fi-hydroxyethyl)-aminobenzenediazonium chloride 4-N-pyrrolidino-benzenediazonium chloride The following specific examples disclose diazo-sensitized formulations which may be employed to coat suitable base materials in making diazotype materials. These examples are given by way of illustration and are not to be considered as limiting of the scope of this invention:

EXAMPLE V A coating solution was prepared by mixing the following ingredients in the following proportions at room temperature:

Water cc 70 Ethylene glycol cc 1.5 Glycerine cc 5.0 Citric acid g 4.0 Thiourea g 3.0

1,3,6-naphthalene trisulfonic acid, sodium salt g 1.0

Z-acetoacetamidoacetamide (from Example II) g 1.8

4 N, N diethylamino benzenediazonium chloride g 1.6

Zinc chloride g" 4.0

This mixture was then diluted to cc. with water, and used to coat stock paper in the usual manner, empolying a doctor blade to remove the excess solution. After drying the coated paper was exposed beneath an appropriate, partially opaqued original. Subsequent development in ammonia vapor produced a yellow dye image on a clear background.

EXAMPLE VI Another coating solution was prepared by mixing the following proportions at room temperature:

Water cc 70 Ethylene glycol cc 1.5 Glycerine cc 5.0 Citric acid g 4.0 Thiourea g 3.0 1,3,6-naphthalene trisulfonic acid, sodium salt g 1.0 2,3-dihydroxy naphthalene-o'sulfonic acid g 1.5

Z-acetoacetamidoacetamide (from Example II) g 0.05 4-N,N-diethylaminobenzenediazonium chloride g 1.6 Zinc chloride g 4.0

tested for shelf life by placing in an oven at F. for 7 three days. When removed no background discoloration was observed. In contrast a diazo formulation using acetoacetanilide as a coupler and another using the diacetoacetamide of ethylenediamine were both found to have back-ground discoloration after only one day under similar conditions.

The work with the new acetoacetamido compounds has indicated that the usual diazo formulations can be used, except of course for the coupler constituent. Substitution of acetoacet couplers embodying this invention for the usual aromatic or aliphatic acetoacetamido compounds produces diazo prints of high color saturation. The tendency to precouple which characterizes conventional couplers of this type has been greatly reduced. Another important aspect of this invention is that the reactivity of this new class of couplers can be closely matched to the coupling activity of other color couplers whereby the new couplers can be readily used in combination with other dyes. Moreover, solution of the precoupling problem permits use of higher concentrations of this new class of couplers in diazo formulations thereby resulting in the formation of dyes of greater intensity.

While the advantages of this invention are of particular significance in blackline diazo products, it is apparent that it relates to yellow, orange and other color products in which acetoacet couplers may be used since enhancement of shelf life is always an important consideration in the facsimile field.

The compounds, embodying this invention, may be applied to plastic layers in organic solvents as well as to paper in aqueous solvents in Examples V and VI.

Having thus described the invention, what is claimed is:

1. Diazotype sensitized material having a support with a light sensitized layer thereon comprising a light sensitive diazonium salt and a 2-acetoacetamido propanediamide coupler.

2. Diazotype sensitized material having a support with a light sensitized layer thereon comprising a light sensitive diazonium salt and a Z-acetoacetamido acetamide coupler.

3. Diazotype sensitized material having a support with a light sensitized layer thereon comprising a light sensitive diazonium salt and a Z-acetoacetamido N,N diethylaceta'mide coupler.

4. A coating solution for making diazo light sensitive materials having a black dye image comprising a benzenediazonium salt, dihydroxy naphthalene sulfonic acid, and an acetoacet compound of the formula:

wherein R is a member of the group consisting of H and an alkyl radical containing 1 to 4 carbon atoms.

5. A coating solution for making diazo light sensitive materials as set forth in claim 4 in which said benzenediazonium salt is 4-N,N-diethylamino benzenediazonium chloride, and in which said acetoacet compound is acetoacetamido acetamide.

6. Coating solution as set forth in claim 4 in which the materials are dissolved in aqueous medium and in which the said sulfonic acid is 2, 3 dihydroxy naphthalene-6- sulfonic acid, and said benzenediazonium salt is 4-N,N diethylamino benzenediazonium chloride.

References Cited UNITED STATES PATENTS 1/1935 Schmidt et al. 9691 X 

